I'm going to be using in a car, a hatchback to be honest, i have looked a lot designs and even asked the advice of a very well known box design over in the UK to design me a box, and i was thinking of building a DB15 to compare against his... ???

ahah the DB15 is what you seek? hrmm... design this we can, sub specs we need. Start with normal 12 DB I would, then modify it to fit 15 inch. Do this by keeping the circle hole in baffle same size, and enlargeing everything else to fit the 15. Directs the sound, the circle hole does. 10 inch diameter it must be to keep baffle working correctly. The 10 and 12 inch DBs' baffles are almost exactly the same from the circle hole in the 12 past and the main baffle piece in the 10 on back.

I believe this 10 inch hole in 12 inch version makes the air move the same as in the 10 inch DB, therefore the porting will work.

Now the moon or thong cut out. This is a problem, I would figure the Surface area of the 10 inch hole, and area of the 12 inch hole and relate them in a ratio:10PA : 12PA (SA = Port Surface Area)----- -----10CA : 12CA (CA = Cone Surface Area)

[quote author=J_Rock link=1126628925/0#5 date=1126735746]yeah I was having fun. so If Tyranacide is around and wants to figure out the area of the thong port of the db12 and the moon port of the db10.... [/quote]

I thought I mentioned in that post... the exact shape for any exponential port is not that important.... geez. As for a simplistic way to design try this..... 2 nails, a string, and a pencil, tie string in loop, place over 2 nails, pull string tight with pencil( point down ) move pencil in counter clock wise direction for ...elipse/oval/4 parts of an exponential shape... OR move pencil in clockwise direction and it will draw out the smile on Yodas face, it will......LOL

Really now, only a few tries with nail spacing and string legnth on scrap paper will suffice to get the size you need...without any math whatsoever. It's the average guys math avoidance trick

[quote author=Slick link=1126628925/0#0 date=1126625325]I have the plans for a Deathbox II, can this plan be scaled up to use on a 15"? Or is it not as easy as that? ???

has anyone tried it out to build a DB 15? ::) [/quote]

sick idea, a 15"b is gonna pound the chit outa everything.personally when scaleing (and you need to know i am probably the least educated here) i would scale everything by the ratio of sub to sub.for example in the 12 inch db the baffle is 13.5 i believe.1.5 inches bigger than the driver. so for a 15 inch version i would make the baffle 16.5, the 10" cut out air flow controll thingie is 10 inches on the 12 inch db 2 inches smaller than the sub, so in the 15" db i would make that cut out 13". now you could scale everythning by the ratio of cone area to cone are, but i like to eat pie?

That seems like a lot of really descriptive free info for a set of plans offered for sale, here. Maybe I'm wrong, but I think we're going too far. A scaling formula is one thing, but I think a drawing and measurements is a bit much.

its not to scale and it only tells people the size of the hole to mount the subs in are. I could deduce much of the same information from the animated pictures on the main site. If anyone else thinks its too much info I will remove them.

[quote author=J_Rock link=1126628925/0#10 date=1126986800]no, you would scale the baffle of the 12 inch db up to fit the 15, except you are gonna need to move the circle hole of the 12db, the 10 inch diameter, down to make room fo rthe 15's basket:

length B would be determined by scaling length C, and length A by the height and size of your 15 inch woofer.

Also notice hole in 15 baffle is same size as 12, which is the same size as a 10db baffle hole.

(sorry about scale)

Tyranacide, I was wondering if you could scale the 12 inch port to the size of a 15 port? based on the area if the 10 inch port and the 12 inch port. 10 inch area= X 12 inch area = Y 15 inch area = Z

X : Y as Y : Z kinda thing? [/quote]

Sorry J Rock, but you seem to have lost me a little i think...

The length for A & C of the 15DB would have to be the length of a 12DB length B scaled by the depth of the subwoofer... slightly confused.. ???

Also so does everyone thing a thong port is better then a arc port on a 15DB....

I have scaled up the plans in an autoCAD program and have only the port to work out and the size and depth of the length A and C as J rock says..but at the mo, bit lost :'(

Oh man I totally messed that up is why you are confused! haha I am a dork.

length A is B scaled up.length c is the shortest possible with you woofer.

Sorry about that I hav eno clue what I even typed before.

I think the 10 inch hole is plenty for the output of the 15. I mean, its just there to channel the air the same way the 10db does. If anything, you could cut several pieces and put different size holes in them....

don't forget there will be a a hair plus a 1/4 differance between the 3/4 MDF and 25mm..Some forget about centering the port because of the 3/4. With the odd size material on one side may effect a the port and a square box.

Just in case you may have overlooked it.

I am really interested in how your 15 turns out and how big the thing is.

id be interested to hear how a 15" deathbox turns out, also you might find some of the plans at www.speakerplans.com interesting, there more based around PA stuff. check out the faq aswell, makes an interesting read...

im gonna buy the plans for a deathbox.... & i happen to remove 4 15" kicker L5's out of a truck & replaced them with mtx 9500's....2 where sold but i have 2 just setting in the shop....what do u guys think about them for my home audio? i have a earthquake pro800 amp to power them with witch is 1100rms@4ohms bridged. the L7's are dual 4ohm coils.

im kinda lost on this "scaling" someone want to help me out?size is not a matter as it well be in a living room

Looking at it all now, if you want to scale a DB, I can help you with some things.

But if you are looking to build an HT sub, check out the Home Theater Section of the forums. There are a few posts there, and a few very knowledgeable posters. They should be able to help out alot more.

So basically, decide if you want to scale a DB for 15s, or build a box specifically for them to use as HT subs.

If they model well, that would be one powerful subwoofer. Those L7's LOVE huge enclosures and IIRC the sealed portion behind the woofer in an SO is ~5ft^3? Yeah, I'd like to see a square sub poking out there.